Turnout for the Women's March has far exceeded expectations and appears to be greater than those who turned up for Donald Trump's inauguration.
Wearing pink, pointy-eared "pussycats" to mock the new president, hundreds of thousands of women took to the streets in the nation's capital and cities around the world Saturday to send Donald Trump an emphatic message that they won't let his agenda go unchallenged over the next four years.
Among the crowds and leading the chants were celebrities including Madonna, Cher, Scarlett Johansson, Emma Watson and Charlize Theron. Pop diva Madonna made an unannounced stage appearance in Washington.
"Welcome to the revolution of love, to the rebellion. To our refusal as women to accept this new age of tyranny," she said as she took the stage, wrapping up hours of speeches by celebrities and rights activists, reports news.com.au.
"It took this horrific moment of darkness to wake us the f*** up.
"They are for birthing new generations of filthy, vulgar, nasty, proud, Christian, Muslim, Buddhist, Sikh, you name it. For new generations of nasty women."
Calling on the already screaming crowd, she finished, "So, if you a nasty woman or you love one who is, let me hear you say, hell yeah!"
Feminist icon Gloria Steinem had a message for the marchers: "Make sure you introduce yourselves to each other and decide what we're going to do tomorrow, and tomorrow and tomorrow. And we're never turning back!"
Among protesters, the anger towards America's new president was remarkable. Most were brandishing handmade signs taking aim at anything from his policies, his Cabinet, tweets that have gotten him into trouble, memorable moments from his presidential campaign, even his physical appearance.
The photos that are continuing to emerge are nothing short of extraordinary.
Metro stations in Washington were jam-packed with people, with many holding handmade signs and wearing pink 'pussy' hats. Others headed there on foot, buses, and other forms of public transport, with many having travelled through the night to be involved.
The turnout in the capital was so big - with some estimating about 500,000 people turned out, double the original estimate - that crowds packed the entire march route, preventing organisers from leading a formal trek toward the White House.
"The crowd stretches so far that there's no room left to march," Interim DC Police Chief Peter Newsham said about Independence Avenue.
Instead, march organizers directed the crowd to take a new route to meet up at the Ellipse, a grassy area between the Washington.
The Women's March is believed to be the biggest inauguration protest in history, with numbers exceeding those who turned up for Trump's inauguration.
"We march today for the moral core of this nation, against which our new president is waging a war," actress America Ferrera told the Washington crowd.
"Our dignity, our character, our rights have all been under attack, and a platform of hate and division assumed power yesterday. But the president is not America. ... We are America, and we are here to stay."
The Women's March in the nation's capital is expected to make its mark on history, taking its place among past marches that led to movements. By comparison, 200,000 people attended the March on Washington in 1963.
In 1967, a march on the Pentagon protesting Vietnam drew a crowd of 100,000, The official rally was expected to feature more than 50 speakers including celebrities Katy Perry, Ashley Judd, America Ferrera, Cher, Scarlett Johansson and Uzo Aduba.
In Utah, Charlize Theron made an appearance alongside Chelsea Handler and Jennifer Beals.
Filmmaker Michael Moore, a march organiser, noted that his copy of the Washington Post was bannered with the headline "Trump Takes Power."
"I don't think so. Here is the power," he said, gesturing to the crowd.
There were also more than 600 "sister marches" planned around the country this weekend, with some of the biggest expected in Boston, New York, Los Angeles and Chicago.
But women, men and children in various cities around the world have also joined in, with huge numbers marching in solidarity in Berlin, London, Paris and Cape Town.
Australia was the scene of the first major march, with an estimated 10,000 walking from Sydney's Hyde Park to Martin Place on Saturday. In New Zealand's capital, Wellington, organisers said about 700 marchers joined forces.
In Chicago, organisers cancelled the march portion of their event for safety reasons after the overflow crowd reached an estimated 150,000.
The women brandished signs with slogans such as "Women won't back down" and "Less fear more love" and decried Trump's stand on such issues as abortion, health care, gay rights, diversity and climate change.
Their message reverberated at demonstrations around the globe, from New York, Philadelphia, Chicago and Los Angeles to Paris, Berlin, London, Prague, Sydney and beyond.
Boston professor Garland Waller, 66, part of the Washington mobilisation, said she was "devastated" after the election and had to take action. "I don't know what to do to make a difference anymore, and this feels like a first step," she said.
Saskia Coenen Snyder, a teacher at the University of South Carolina who came to a rally in Columbia, said: "I'm not sure we could have picked a more irresponsible, misogynistic and dangerous man to be president."
Officials said the crowd in Washington could be more than half a million people, more than double expectations. The event appeared to have attracted more people than Trump's inauguration on Friday, based on figures from transportation officials.
More than 600 "sister marches" were planned around the world, and plenty of men were part of the tableau, too. Organisers estimated 3 million people would march worldwide. Seventy-one-year-old Allan Parachini, who travelled from Hawaii to the Washington march, called it "the most impressive crowd I've seen since Woodstock."
Retired teacher Linda Lastella, 69, who came to Washington from Metuchen, New Jersey, said she had never marched before but felt the need to speak out when "many nations are experiencing this same kind of pullback and hateful, hateful attitudes." "It just seemed like we needed to make a very firm stand of where we were," she said.
As the demonstrators rallied alongside the National Mall, Trump opened his first full day as president by attending a prayer service at the Washington National Cathedral, a tradition for the day after inauguration, and later visited the CIA.
As he travelled around town, his motorcade passed large groups of protesters that would have been hard to miss.
Marlita Gogan, who came to Washington from Houston for the inauguration, said police advised her family not to wear their "Make America Great Again Hats" as they walked through crowds of protesters while playing tourist on Saturday.
"I think it's very oppressive," she said of the march atmosphere. "They can have their day, but I don't get it."
On the streets, feminist leader Gloria Steinem described the worldwide mobilisation as "the upside of the downside: This is an outpouring of energy and democracy like I have never seen in my very long life."
"Sometimes we must put our bodies where our beliefs are," she told the crowd, labelling Trump an "impossible president."
Hillary Clinton, who lost to Trump, took to Twitter to thank the participants for "standing, speaking and marching for our values."
The marches displayed a level of enthusiasm that Clinton herself was largely unable to generate during her campaign against Trump, when she won the popular vote but he outdistanced her in the electoral vote.
At rallies around the world, many participants wore hand-knit "pussycats" - a message of female empowerment aimed squarely at Trump's crude boast about grabbing women's genitalia.
They "ain't for grabbing," actress Ashley Judd told the Washington crowd.
The marches were a magnet for A-list celebrities, unlike Trump's inauguration, which had a deficit of top performers.
Cher, in the nation's capital, said Trump's ascendance has people "more frightened maybe than they're ever been."
In Park City, Utah, it was Charlize Theron leading demonstrators in a chant of "Love, not hate, makes America great."
In New York, actresses Helen Mirren and Cynthia Nixon and Whoopi Goldberg joined a crowd of protesters marching to Trump's local home.
In Paris, thousands rallied in the Eiffel Tower neighbourhood in a joyful atmosphere, singing and carrying posters reading "We have our eyes on you Mr. Trump" and "With our sisters in Washington."
Hundreds gathered in Prague's Wenceslas Square in freezing weather, mockingly waving portraits of Trump and Russia's Vladimir Putin.
"We are worried about the way some politicians talk, especially during the American elections," said organiser Johanna Nejedlova.
In Sydney, thousands of Australians gathered in solidarity in Hyde Park. One organiser said hatred, bigotry and racism are not only America's problems.
The rallies were a peaceful counterpoint to the window-smashing unrest that unfolded on Friday when self-described anarchists tried to disrupt the inauguration.
Police used pepper spray and stun grenades against demonstrators. More than 200 people were arrested.
- Associated Press Writers Alanna Durkin Richer, Brian Witte, Matthew Barakat, and David Dishneau in Washington contributed to this report.